NovaBACKUP: VMware Plug-In

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1 NovaBACKUP: VMware Plug-In Nathan Fouarge / NovaStor / April NovaStor, all rights reserved. All trademarks are the property of their respective owners. Features and specifications are subject to change without notice. The information provided herein is provided for informational and planning purposes only.

2 Executive Summary This document will describe multiple things including: how the VMware plug-in for NovaBACKUP works with VMware ESX(i) servers along with vsphere, how to configure NovaBACKUP to connect to the VMware infrastructure, what needs to be setup on the VMware infrastructure, and how the backup and restore process works with NovaBACKUP. Requirements NovaBACKUP BE must be installed on a supported operating system. The machine that with NovaBACKUP BE on it needs to have connectivity to either the vsphere server or the ESX(i) server. NovaBACKUP BE can alternatively be installed on the vsphere server, or on a Virtual Machine. Version 4.1 and 5.0 of ESX(i) and vsphere licensed with the vstorage APIs are the currently supported versions of software that the VMware plug-in for NovaBACKUP BE will communicate with. In order to do incremental or differential backups the communication must go through vsphere. The machine that has NovaBACKUP BE installed on it also has to have enough local disk space to temporarily hold all the Virtual Machines that you want to backup in one backup job. Copyright NovaStor

3 Configuration of NovaBACKUP After NovaBACKUP BE has been installed, open the software and click on the Default Settings link on the left hand side of the Home screen. Then go to the VMware Server tab in the dialog that comes up, and click Add to add a new connection to a ESX(i) or vsphere server. Copyright NovaStor

4 Selection of Virtual Machines After the ESX(i) or vsphere server connections have been added to the configuration of NovaBACKUP BE, the backup tab will need to be refreshed, so that a connection to the ESX(i) or vsphere server can be established. This may be accomplished by either pressing F5 on the keyboard or closing and reopening the software in the Backup tab. Once properly refreshed, the screen should appear as below, and the VMware node should be selectable. Navigating to this node will show all the ESX(i) or vsphere servers configured in NovaBACKUP. Clicking on each ESX(i) or vsphere server node will display the Virtual Machines that are available to backup. These machines may be backed up individually, or all of them may be backed up at once. Copyright NovaStor

5 Configuration of Backup Mode Once the Virtual Machines are selected for backup, it is important to configure the settings for the backup job. Clicking on the settings button on the backup tab will show the Advanced Settings dialog (shown below). The type of backup performed is set using the Backup Mode dropdown. If Full mode is selected, the entire virtual machine will be backed up each time this script runs. If incremental is selected, then a block level incremental from the last backup of the virtual machine will be performed each time this script runs. If differential is selected, a block level differential backup is run from the last full backup of the Virtual Machine. For the sake of a Virtual Machine a snapshot backup is the same as a full backup, and functions no differently. If attempting to run incremental or differential backups of a Virtual Machine, NovaBACKUP must be connecting to a vsphere server and the Virtual Machine must be configured to support incremental and differential backups. Copyright NovaStor

6 Configuration of Virtual Machines for Incremental and Differential backups As a default on a new Virtual Machine, the tracking of changed blocks (CBT) isn't enabled as CBT will slow down the execution of a Virtual Machine. To enable CBT it is necessary to install the latest version of VMware tools on the Virtual Machine. The Virtual Machine has to have hardware version 7 or later. There will normally have to be some changes done to the Virtual Machine configuration as well. The main parameter that has to be changed or added is "ctkenabled" with the value "true", but for each disk on which changes should be tracked, CBT has to be enabled separately. For example for the disk device scsi:0:1 it is necessary to add a parameter "scsi0:1.ctkenabled" with the value "true". If CBT isn't enabled at all or for a specific device, the device will be backed up in full mode every time, incremental and differential backup of a disk that does not have this enable is not possible as the information about changed blocks are not available. Copyright NovaStor

7 How to Restore a Virtual Machine Restoring a Virtual Machine is quite easy. Simply select the Virtual Machine to restore in the Restore UI and click the restore button. If a Virtual Machine of the same name that you are going to restore already exists on the ESX(i) or vsphere server that you are restoring to, the NovaBACKUP BE software will automatically create the Virtual Machine in your inventory with the name of the Virtual Machine that you are restoring along with a timestamp at the end of the name of the Virtual Machine as to not cause conflicts with the existing Virtual Machine. Copyright NovaStor

8 Advanced Restore with Differential and Incremental Backups of Virtual Machines Restoring from a differential or incremental backup of a Virtual Machine requires some thought and knowledge of how things were backed up. The restore of a differential or incremental backup of a Virtual Machine is also performed in a reverse order of how other restore operations are performed by traditional backup software. Performing a successful restore means understanding the point in time that the system is being restored to, and having a good understanding of how the restore process works. In the case of an incremental backup, the process is simple. Select the last incremental backup corresponding to the restore point as would be done with a traditional backup. It is the necessary to make note of every incremental backup that occurred between the current point, and the original full backup. The restore order is to restore the latest (furthest from the full backup) incremental backup first, then restore each in reverse order until reaching the full backup, at which point the full backup should be restored. In the case of a differential backup, the process is even easier. First restore the differential backup from the desired date, then restore the full backup before it. In the case of a mixed backup, it is necessary to first apply any incremental backups since your last differential, then the differential, then the full backup. This process seems to be backwards, but because each of these restores is a block level restore, the process is generally very fast. In general all the snapshots that were temporarily created during the restore should be removed on completion of the restore. If not, it may be necessary to remove the snapshots manually on the Virtual Machine through the vsphere client interface. Copyright NovaStor

9 How the backup and restore process works The backup operation of the NovaBACKUP BE first contacts the ESX(i) or vsphere server and begins a snapshot of the Virtual Machine(s) that are being backed up. After that is completed, NovaBACKUP BE then starts to stage the Virtual Machine to a temporary location on the local machine NovaBACKUP BE is installed on. This temporary location is configured in the Advanced Settings tab of the Default Settings that can be accessed on the Home tab of the NovaBACKUP BE software, a restart of the NovaBACKUP BE service is needed to apply the change, if this folder is changed. The temporary file that is created in this folder will have an extension of ".nvm" in a Vdata folder for each selected Virtual Machine in the backup job. Finally, NovaBACKUP BE will backup this temporary file to the device that is selected in the backup job and once that has completed, the temporary files will be cleaned up. The restore operation of the NovaBACKUP BE first restores the Virtual Machine to the temporary file that it was originally backed up as. NovaBACKUP BE will then contact the ESX(i) or vsphere server, and tell the server to create a Virtual Machine with the parameters that the original Virtual Machine was backed up with. Next, NovaBACKUP BE will stream the Virtual Machine to the server. Once that is done NovaBACKUP BE will then do clean up on both the ESX(i) or vsphere server along with the temporary file it created during the restore. Copyright NovaStor

10 Considerations and known issues If the virtual plug-in is going to be used when backing up to an xsp device full, incremental, and differential backups act differently. If you plan on using the built in incremental or differential options that VMware exposes you need to add nvm to the CompressedFileTypes.txt in the configuration of the xsp device you will be backing up to. This will make the xsp device not use compression or FastBIT on the VMware file. This is needed only when you are going to use the incremental and differential backup option with the VMware plug-in. If full backups are always done then FastBIT will determine the differences between the two full backups and only send the changed parts of the full backups. Doing it that way will take more local storage, and can conceivably take longer, but restoring is very easy as you would just have to restore the latest file and not have to deal with restoring different versions to get to the current version. Virtual machines that are contained in a Vapp container cannot be seen or backed up when connected to a vsphere server, instead if you connect directly to the ESX(i) server you will be able to see and backup those VMs. Restoring directly to an alternate ESX(i) or vsphere server is only supported if the name of the server is the same as when the VM was backed up currently. Copyright NovaStor